National Agricultural Imagery Program (NAIP) - quarter-quadrangle index
U S Department of Agriculture
Index of USGS quarter-quadrangles (3.75 minute) covering Pennsylvania used for 2004 National Agricultural Imagery program (NAIP) images. The polygons are attributed with information pertaining to USGS quadrangle names and quarter-quad designations. The polygons are also attributed with the initial identifying portion of the 2004 NAIP image file names.